Xist Expression Research Articles

Sex differences and immune correlates of Long Covid development, symptom persistence, and resolution.

Sex differences have been observed in acute coronavirus disease 2019 (COVID-19) and Long Covid (LC) outcomes, with greater disease severity and mortality during acute infection in males and greater proportions of females developing LC. We hypothesized that sex-specific immune dysregulation contributes to LC pathogenesis. To investigate the immunologic underpinnings of LC development and symptom persistence, we performed multiomic analyses on blood samples obtained during acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and 3 and 12 months after infection in a cohort of 45 participants who either developed LC or recovered. Several sex-specific immune pathways were associated with LC. Males who would later develop LC exhibited increases in transforming growth factor-β (TGF-β) signaling during acute infection, whereas females who would go on to develop LC had reduced TGFB1 expression. Females who developed LC demonstrated increased expression of XIST, an RNA gene implicated in autoimmunity, during acute infection compared with females who recovered. Many immune features of LC were also conserved across sexes, such as alterations in monocyte phenotype and activation state. Nuclear factor κB (NF-κB) transcription factors were up-regulated in many cell types at acute and convalescent time points. Those with ongoing LC demonstrated reduced ETS1 expression across lymphocyte subsets and elevated intracellular IL-4 in T cell subsets, suggesting that ETS1 alterations may drive aberrantly elevated T helper cell 2-like responses in LC. Altogether, this study describes multiple innate and adaptive immune correlates of LC, some of which differ by sex, and offers insights toward the pursuit of tailored therapeutics.

Significance of serum lncRNA XIST in chronic obstructive pulmonary disease and its progression to pulmonary heart disease

BackgroundChronic obstructive pulmonary disease (COPD) has become one of the major death-related causes. Chronic pulmonary heart disease (CPHD) is an adverse complication of COPD causing poor prognosis of patients. This study evaluated the role of lncRNA XIST in COPD and CPHD aiming to identify a potential biomarker for the screening and prediction of COPD.MethodsThe study enrolled 127 COPD patients, including 73 patients occurred CPHD with 76 healthy individuals as the control group. The expression of XIST was evaluated by PCR and compared between COPD patients with different severity, grades, and complications. The diagnostic and prognostic values of XIST in COPD and CPHD were assessed by ROC and Kaplan-Meier analyses.ResultsSignificant upregulation of XIST was observed in the serum of COPD patients relative to healthy individuals, which distinguished COPD patients and showed a correlation with the respiratory and pulmonary function of COPD patients. COPD patients with acute exacerbations and CPHD showed a higher expression level. Increasing serum XIST discriminated COPD patients combined CPHD and positively correlated with right ventricular hypertrophy and pulmonary hypertension. Higher serum XIST levels could indicate the adverse 3-year prognosis of COPD patients, especially for COPD patients combined with CPHD.ConclusionUpregulated XIST served as a biomarker for screening COPD and predicting adverse prognosis of COPD and COPD patients with CPHD.

Inflammation-Associated Long Non-Coding RNAs (lncRNAs) in Chronic Viral Hepatitis- Associated Hepatocellular Carcinoma.

This study aimed to identify the expression profile and prognostic significance of inflammation-associated lncRNAs in chronic viral hepatitis (CVH) and CVH-associated hepatocellular carcinoma (CVH-HCC). In the first step, lncRNA expression analysis was performed by real-time polymerase chain reaction (RT-PCR) using an array panel of 84 inflammation-associated lncRNAs in 48 formalin-fixed paraffin-embedded (FFPE) tissue samples (12 CVH-HCC, 12 peritumoral cirrhotic parenchyma, 12 nontumoral cirrhotic CVH parenchyma, 12 normal liver samples). In the second step, 7 lncRNAs (DLEU2, HOTAIR, LINC00635, LINC00662, RP11-549J18.1, SNHG16 and XIST) were chosen for RT-PCR assay testing in 72 samples (24 CVH-HCC, 24 peritumoral cirrhotic parenchyma, 24 nontumoral cirrhotic CVH parenchyma samples). Fifty-six inflammation-associated lncRNAs were significantly up-regulated in the peritumoral cirrhotic parenchyma compared to the normal liver. Expression of 71 lncRNAs was significantly higher in peritumoral cirrhotic parenchyma compared to cirrhotic CVH parenchyma. DLEU2 and SNHG16 were up-regulated both in the tumor and peritumoral cirrhotic parenchyma compared to cirrhotic CVH parenchyma. Expression of LINC00662 was significantly higher in CVH-HCC than in cirrhotic CVH parenchyma. Expression of XIST was also increased in both tumor and peritumoral parenchyma samples, albeit without statistical significance. No significant association was found between lncRNA expressions and survival. Inflammation-associated lncRNAs DLEU2, SNHG16, LINC00662, and XIST are candidate diagnostic biomarkers in CVH-HCC. More evidence is needed to prove their utility as prognostic markers.

Cdk8 and Hira mutations trigger X chromosome elimination in naive female hybrid mouse embryonic stem cells

Mouse embryonic stem cells (ESCs) possess a pluripotent developmental potential and a stable karyotype. An exception is the frequent loss of one X chromosome in female ESCs derived from inbred mice. In contrast, female ESCs from crosses between different Mus musculus subspecies often maintain two X chromosomes and can model X chromosome inactivation. Here we report that combined mutations of Hira and Cdk8 induce rapid loss of one X chromosome in a Mus musculus castaneus hybrid female ESC line that originally maintains two X chromosomes. We show that MEK1 inhibition, which is used for culturing naive pluripotent ESCs is sufficient to induce X chromosome loss. In conventional ESC media, Hira and Cdk8 mutant ESCs maintain both X chromosomes. Induction of X chromosome loss by switching to naive culture media allows us to perform kinetic measurements for calculating the chromosome loss rate. Our analysis shows that X chromosome loss is not explained by selection of XO cells, but likely driven by a process of chromosome elimination. We show that elimination of the X chromosome occurs with a rate of 0.3% per cell per division, which exceeds reported autosomal loss rates by 3 orders of magnitude. We show that chromosomes 8 and 11 are stably maintained. Notably, Xist expression from one of the two X chromosomes rescues X chromosomal instability in ΔHiraΔCdk8 ESCs. Our study defines mutations of Hira and Cdk8 as molecular drivers for X chromosome elimination in naive female ESCs and describes a cell system for elucidating the underlying mechanism.

7972 A Shared Phenotype, Transcriptome, and Methylome in Turner Syndrome Across Various Karyotypes with Concurrent Chronic Neutrophil Activation

Abstract Disclosure: J. Just: None. L. Ridder: None. E. Johannsen: None. H. Christensen: None. A. Skakkebæk: None. C.H. Gravholt: None. Turner syndrome (TS) is a clinical diagnosis with a karyotype containing one X chromosome and complete or partial absence of the second X chromosome. TS is typically associated with clinical manifestations such as short stature, hypergonadotropic hypogonadism and metabolic conditions. The genome-wide changes in females with TS affect both transcriptome and methylome. Historically, genomic studies have primarily focused on the 45,X karyotype, leaving the impact of other karyotypes unexplored. Only 35-45% of the entire TS population has the 45,X karyotype, while the remaining TS women have a range of other karyotypes - i.e. 45,X/46,XX, 46,X,i(Xq), 46,X,i(Xp), 45,X/46,XY, ring X. This study aimed to bridge this gap by comparing TS individuals with the standard 45,X karyotype (TS 45,X) (n = 32) to those with alternative karyotypic forms (TS other karyotypes) (n = 24), alongside age-matched 46,XX controls (n = 33). Specifically, we analyzed the DNA methylation and gene expression profiles from whole-blood samples and explored the genetic and clinical similarities between these groups. Overall findings revealed a shared phenotype and an identical autosomal transcriptome and methylome between TS 45,X and TS other karyotypes. Furthermore, TS 45,X and TS other karyotypes shared the same expression profile for all pseudoautosomal 1 (PAR1) genes on the X chromosome. In addition, the expression of XIST from the q-arm of the X chromosome did not affect the autosomal transcriptome or methylome. Thus, the X chromosomal p-arm, and perhaps in particular PAR1, appear to be a main driver influencing the genome-wide transcriptome and methylome Combining DNA methylation, gene expression and white blood cell counts, we observed a higher neutrophil count (p < 0.01), and increased neutrophil activation in the combined TS group. The increased neutrophil activity, based on increased gene expression of neutrophil activation markers (myeloperoxidase, neutrophil elastase, S100A8/9, p < 0.01), suggested a pathological activation of neutrophils with concomitant release of pro-inflammatory mediators. We further validated the increase of neutrophils in TS women in an independent cohort using flow cytometry (p < 0.01). Emerging evidence has highlighted the substantial involvement of neutrophils in chronic inflammatory processes associated with metabolic diseases such as obesity and diabetes, which triggers a sustained low-grade inflammation partially driven by activated neutrophils. The neutrophil increase and activation in TS women may offer an explanation for this phenotypic trait observed in TS women. Therefore, identifying TS women with increased neutrophil activation in order to initiate anti-inflammatory treatment earlier could potentially mitigate the progression towards more severe metabolic disturbances and associated co-morbidities. Presentation: 6/1/2024

Diagnostic Value of lncRNA XIST in Saliva for Early Peri-Implantitis.

To analyse the relative expression and diagnostic potential of lncRNA XIST (XIST) in peri-implantitis, and explore the related mechanism of XIST in peri-implantitis. XIST expression in saliva of patients with peri-implantitis was detected by qRT-PCR. The diagnostic significance of XIST in peri-implantitis was assessed by ROC curve. Clinical indicators of the included patients were collected and the correlation between XIST levels and peri-implant indicators was determined by Pearson correlation analysis. Bioinformatic prediction and luciferase reporter assay confirmed the targeting relationship of XIST with downstream factors. Salivary XIST levels were obviously higher in patients with peri-implantitis than in the healthy control group, and the AUC value for identifying patients was 0.8742 with a sensitivity and specificity of 83.5% and 81.4%. Patients in the peri-implantitis group had higher levels of plaque index (PLI), sulcus bleeding index (SBI) and probing depth (PD) than those in the healthy control group, and the expression of XIST was positively correlated with PLI, SBI, and PD levels. In addition, miR-150-5p was confirmed to be a potential downstream target of XIST. XIST was overexpressed in the saliva of patients with peri-implantitis and correlated with the severity of the disease. XIST has high diagnostic significance for detecting peri-implantitis.

Sex differences and immune correlates of Long COVID development, persistence, and resolution.

Sex differences have been observed in acute COVID-19 and Long COVID (LC) outcomes, with greater disease severity and mortality during acute infection in males and a greater proportion of females developing LC. We hypothesized that sex-specific immune dysregulation contributes to the pathogenesis of LC. To investigate the immunologic underpinnings of LC development and persistence, we used single-cell transcriptomics, single-cell proteomics, and plasma proteomics on blood samples obtained during acute SARS-CoV-2 infection and at 3 and 12 months post-infection in a cohort of 45 patients who either developed LC or recovered. Several sex-specific immune pathways were associated with LC. Specifically, males who would develop LC at 3 months had widespread increases in TGF-β signaling during acute infection in proliferating NK cells. Females who would develop LC demonstrated increased expression of XIST, an RNA gene implicated in autoimmunity, and increased IL1 signaling in monocytes at 12 months post infection. Several immune features of LC were also conserved across sexes. Both males and females with LC had reduced co-stimulatory signaling from monocytes and broad upregulation of NF-κB transcription factors. In both sexes, those with persistent LC demonstrated increased LAG3, a marker of T cell exhaustion, reduced ETS1 transcription factor expression across lymphocyte subsets, and elevated intracellular IL-4 levels in T cell subsets, suggesting that ETS1 alterations may drive an aberrantly elevated Th2-like response in LC. Altogether, this study describes multiple innate and adaptive immune correlates of LC, some of which differ by sex, and offers insights toward the pursuit of tailored therapeutics.

Clinical significance of lncRNA XIST expression in cholangiocarcinoma and its effect on cell migration and invasion

BackgroundCholangiocarcinoma is a malignant tumor that occurs in the bile duct system, and the prognosis of patients is poor. Currently, research suggests that long non-coding RNAs (lncRNAs) in the treatment and prevention of cholangiocarcinoma. This study primarily focuses on the regulation and potential mechanism of the lncRNA XIST (XIST) in cholangiocarcinoma. MethodsThe levels of XIST and miR-126–3p in cholangiocarcinoma tissues and cells were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Cell transfection status, including migration and invasion, was examined via the Transwell method. The relationship between XIST and miR-126–3p was observed by dual-luciferase gene reporter assay and verified by rescue assays. Additionally, the prognostic significance of XIST in cholangiocarcinoma was determined using Kaplan-Meier and multivariate Cox regression analyses. ResultsXIST expression was increased in cholangiocarcinoma, while miR-126–3p was decreased, in both tissues and cells. The successful construction of silencing XIST was found to inhibit the count of cell migration and invasion. XIST directly targeted miR-126–3p to regulate the progression of cholangiocarcinoma. ConclusionXIST sponging miR-126–3p inhibited the progression of cholangiocarcinoma and improved the prognosis for patients. This finding provides new insights and opportunities for future studies on cholangiocarcinoma prognostic biomarkers.

X‑chromosome loss rescues Sertoli cell maturation and spermatogenesis in Klinefelter syndrome

Klinefelter syndrome (47,XXY) causes infertility with a testicular histology comprising two types of Sertoli cell-only tubules, representing mature and immature-like Sertoli cells, and occasionally focal spermatogenesis. Here, we show that the immature-like Sertoli cells highly expressed XIST and had two X-chromosomes, while the mature Sertoli cells lacked XIST expression and had only one X-chromosome. Sertoli cells supporting focal spermatogenesis also lacked XIST expression and the additional X-chromosome, while the spermatogonia expressed XIST despite having only one X-chromosome. XIST was expressed in Sertoli cells until puberty, where a gradual loss was observed. Our results suggest that a micro-mosaic loss of the additional X-chromosome is needed for Sertoli cells to mature and to allow focal spermatogenesis.

Loss of One X and the Y Chromosome Changes the Configuration of the X Inactivation Center in the Genus Tokudaia

Introduction: X chromosome inactivation (XCI) is an essential mechanism for dosage compensation between females and males in mammals. In females, XCI is controlled by a complex, conserved locus termed the X inactivation center (Xic), in which the lncRNA Xist is the key regulator. However, little is known about the Xic in species with unusual sex chromosomes. The genus Tokudaia includes three rodent species endemic to Japan. Tokudaia osimensis and Tokudaia tokunoshimensis lost the Y chromosome (XO/XO), while Tokudaia muenninki (TMU) acquired a neo-X region by fusion of the X chromosome and an autosome (XX/XY). We compared the gene location and structure in the Xic among Tokudaia species. Methods: Gene structure of nine genes in Xic was predicted, and the gene location and genome sequences of Xic were compared between mouse and Tokudaia species. The expression level of the gene was confirmed by transcripts per million calculation using RNA-seq data. Results: Compared to mouse, the Xic gene order and location were conserved in Tokudaia species. However, remarkable structure changes were observed in lncRNA genes, Xist and Tsix, in the XO/XO species. In Xist, important functional repeats, B-, C-, D-, and E-repeats, were partially or completely lost due to deletions in these species. RNA-seq data showed that female-specific expression patterns of Xist and Tsix were confirmed in TMU, however, not in the XO/XO species. Additionally, three deletions and one inversion were confirmed in the intergenic region between Jpx and Ftx in the XO/XO species. Conclusion: Our findings indicate that even if the Xist and Tsix lncRNAs are expressed, they are incapable of producing a successful and lasting XCI in the XO/XO species. We hypothesized that the significant structure change in the intergenic region of Jpx-Ftx resulted in the inability to perform the XCI, and, as a result, a lack of Xist expression. Our results collectively suggest that structural changes in the Xic occurred in the ancestral lineage of XO/XO species, likely due to the loss of one X chromosome and the Y chromosome as a consequence of the degradation of the XCI system.

Establishment and maintenance of random monoallelic expression.

This Review elucidates the regulatory principles of random monoallelic expression by focusing on two well-studied examples: the X-chromosome inactivation regulator Xist and the olfactory receptor gene family. Although the choice of a single X chromosome or olfactory receptor occurs in different developmental contexts, common gene regulatory principles guide monoallelic expression in both systems. In both cases, an event breaks the symmetry between genetically and epigenetically identical copies of the gene, leading to the expression of one single random allele, stabilized through negative feedback control. Although many regulatory steps that govern the establishment and maintenance of monoallelic expression have been identified, key pieces of the puzzle are still missing. We provide an overview of the current knowledge and models for the monoallelic expression of Xist and olfactory receptors. We discuss their similarities and differences, and highlight open questions and approaches that could guide the study of other monoallelically expressed genes.

How does the Xist activator Rlim/Rnf12 regulate Xist expression?

The long non-coding RNA (lncRNA) Xist is crucially involved in a process called X chromosome inactivation (XCI), the transcriptional silencing of one of the two X chromosomes in female mammals to achieve X dosage compensation between the sexes. Because Xist RNA silences the X chromosome from which it is transcribed, the activation of Xist transcription marks the initiation of the XCI process and thus, mechanisms and players that activate this gene are of central importance to the XCI process. During female mouse embryogenesis, XCI occurs in two steps. At the 2-4 cell stages imprinted XCI (iXCI) silences exclusively the paternally inherited X chromosome (Xp). While extraembryonic cells including trophoblasts keep the Xp silenced, epiblast cells that give rise to the embryo proper reactivate the Xp and undergo random XCI (rXCI) around implantation. Both iXCI and rXCI are dependent on Xist. Rlim, also known as Rnf12, is an X-linked E3 ubiquitin ligase that is involved in the transcriptional activation of Xist. However, while data on the crucial involvement of Rlim during iXCI appear clear, its role in rXCI has been controversial. This review discusses data leading to this disagreement and recent evidence for a regulatory switch of Xist transcription in epiblasts of implanting embryos, partially reconciling the roles of Rlim during Xist activation.

XIST and MUC1-C form an auto-regulatory pathway in driving cancer progression

The long non-coding RNA X-inactive specific transcript (lncRNA XIST) and MUC1 gene are dysregulated in chronic inflammation and cancer; however, there is no known interaction of their functions. The present studies demonstrate that MUC1-C regulates XIST lncRNA levels by suppressing the RBM15/B, WTAP and METTL3/14 components of the m6A methylation complex that associate with XIST A repeats. MUC1-C also suppresses the YTHDF2-CNOT1 deadenylase complex that recognizes m6A sites and contributes to XIST decay with increases in XIST stability and expression. In support of an auto-regulatory pathway, we show that XIST regulates MUC1-C expression by promoting NF-κB-mediated activation of the MUC1 gene. Of significance, MUC1-C and XIST regulate common genes associated with inflammation and stemness, including (i) miR-21 which is upregulated across pan-cancers, and (ii) TDP-43 which associates with the XIST E repeats. Our results further demonstrate that the MUC1-C/XIST pathway (i) is regulated by TDP-43, (ii) drives stemness-associated genes, and (iii) is necessary for self-renewal capacity. These findings indicate that the MUC1-C/XIST auto-regulatory axis is of importance in cancer progression.

Circulating long noncoding RNA, Zfpm2-As1, and XIST based on medical data analysis are potential plasma biomarkers for gastric cancer diagnosis.

Long noncoding RNAs (lncRNAs) participate in diseases, especially tumorigenesis, including gastric cancer (GC). Although lncRNAs in GC tissues have been extensively studied in previous research, the possible significance of circulating lncRNAs in diagnosing GC is still unknown. The present work investigated lncRNAs ZFPM2-AS1 and XIST with high expression in GC tissues proved as potential plasma biomarkers from 20 early GC cases, 100 GC cases, and 90 normal subjects. The possible correlation between ZFPM2-AS1 and XIST expression levels was analyzed with general characteristics and clinicopathological features. The performance in diagnosis was assessed according to receiver operating characteristic (ROC) analysis. According to the results, XIST and ZFPM2-AS1 expression remarkably increased within GC plasma relative to normal subjects (P< 0.01); besides, lncRNA XIST expression after surgery had a tendency of downregulation compared with preoperative levels (P< 0.05). Moreover, the area under ROC curve (AUC) values were 0.62 for ZFPM2-AS1 and 0.68 for XIST, while the pooled AUC value of CA-724 and two lncRNAs was 0.751. Circulating lncRNAs ZFPM2-AS1 and XIST can serve as the candidate plasma biomarkers used to diagnose GC.

LncRNA XIST promotes neovascularization in diabetic retinopathy by regulating miR-101-3p/VEGFA.

This study sought to investigate the regulation of long noncoding RNA (lncRNA) XIST on the microRNA (miR)-101-3p/vascular endothelial growth factor A (VEGFA) axis in neovascularization in diabetic retinopathy (DR). Serum of patients with DR was extracted for the analysis of XIST, miR-101-3p, and VEGFA expression levels. High glucose (HG)-insulted HRMECs and DR model rats were treated with lentiviral vectors. MTT, transwell, and tube formation assays were performed to evaluate cell viability, migration, and angiogenesis, and ELISA was conducted to detect the levels of inflammatory cytokines. Dual-luciferase reporter, RIP, and RNA pull-down experiments were used to validate the relationships among XIST, miR-101-3p, and VEGFA. XIST and VEGFA were upregulated and miR-101-3p was downregulated in serum from patients with DR. XIST knockdown inhibited proliferation, migration, vessel tube formation, and inflammatory responsein HG-treated HRMECs, whereas the above effects were nullified by miR-101-3p inhibition or VEGFA overexpression. miR-101-3p could bind to XIST and VEGFA. XIST promoted DR development in rats by regulating the miR-101-3p/VEGFA axis. LncRNA XIST promotes VEGFA expression by downregulating miR-101-3p, thereby stimulating angiogenesis and inflammatory response in DR.

Dysregulation of the Long Noncoding RNA X-Inactive–Specific Transcript Expression in Male Patients with Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a sex-biased disease with female gender as a significant risk factor. Recently, we reported that increased expression of the long non-coding (lnc)RNA Xist, as induced by an intersectin-1s protein fragment with proliferative potential (EHITSN), may explain the sexual dimorphism of female pulmonary artery endothelial cells (ECs) and at least in part, the imbalance sex/ratio of PAH.Xist is essential for X-chromosome inactivation and dosage compensation of X-linked genes. Increased Xist expression was also detected in a subset of ECs and lung tissue samples of male PAH patients. The role of different Xist expression levels in ECs of male PAH patients (ECPAH) was studied in several lines of male ECPAH in conjunction with molecular, biochemical, morphological, and functional approaches. Male ECPAH showed on average 10.3-fold increase in high Xist vs. low Xist, a significant association between Xist levels and their proliferative potential, and a heterogeneous methylation of the Xist/Tsix locus. Interestingly, Xist up-regulation in male ECPAH decreases the expression of Klf2, via EHITSN interaction with EZH2, the catalytic subunit of the polycomb repressive complex 2. Moreover, the studies demonstrate that EHITSN-triggered p38/Elk1/c-Fos signaling is a pathological mechanism central to ECPAH proliferation and the dynamic crosstalk with cell cycle regulatory proteins ccna1/ccnd2, and Xist-EZH2-Klf2 interaction participate directly and differentially in establishing the proliferative profile of male ECPAH.

Polysaccharides from Dendrobium officinale delay diabetic kidney disease interstitial fibrosis through LncRNA XIST/TGF-β1

PurposeRenal interstitial fibrosis is a pathological manifestation of the progression of diabetic kidney disease (DKD). Dendrobium officinale polysaccharides (DOP), one of the major active components of Dendrobium officinale, have hypoglycemic and hypolipidemic effects and are used clinically to treat diabetes. However, the role of DOP in delaying DKD progression remains unclear. This study aimed to explore the potential mechanisms by which DOP delays DKD renal interstitial fibrosis. MethodsUsing db/db mice as a model of DKD, we administered DOP by gavage and observed its therapeutic effectiveness. Employing ASO technology, we knocked down lncRNA XIST expression in kidney tissues and detected the expression of lncRNA XIST, TGF-β1, and renal interstitial fibrosis-related molecules. ResultsDOP was primarily composed of monosaccharides, with 91.57% glucose and 1.41% mannose, forming a spheroid-like structure. It has a high polydispersity index with an Mw/Mn of 6.146, and the polysaccharides are mainly connected by 4-Man(p) and 4-Glc(p) linkages. In the kidneys of db/db mice, lncRNA XIST and TGF-β1 are highly expressed; however, their expression is significantly reduced after gastric infusion with DOP, and upon knockdown of lncRNA XIST, it might delay the progression of renal interstitial fibrosis in DKD. ConclusionDOP may delay the progression of DKD renal interstitial fibrosis through the regulation of the LncRNA XIST/TGF-β1 related fibrotic pathway. This provides a new perspective for clinical strategies to delay the progression of DKD renal interstitial fibrosis.

LncRNA XIST Protects Against Polycystic Ovary Syndrome via the Regulation of miR-212-3p/RASA1 Axis.

The polycystic ovary syndrome (PCOS), a common endocrine disorder, is mainly related to infertility. Moreover, it is characterized by promoted androgen, suppressed ovulation and insulin resistance. Long non-coding RNA X inactive specific transcript (lncRNA XIST), known as an oncogene or a cancer inhabited factor, is involved in several disease. However, the diagnostic mechanisms of lncRNA XIST in PCOS have not been clarified. Our study aimed to explain whether lncRNA XIST regulates KGN cells proliferation and apoptosis via microRNA (miR)-212-3p/RASA1 axis in PCOS. Levels of lncRNA XIST, miR-212-3p and RASA1 in KGN cells were detected through reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay. Fluorescence in situ Hybridization (FISH) was performed to confirm the expression of lncRNA XIST and miR-212-3p in KGN cells. StarBase and dual-luciferase reporter assay were applied for exploring the interaction between miR-212-3p and RASA1. Cell viability, apoptosis, protein expression of Bcl-2 and Bax were assessed by MTT, flow cytometry analysis, RT-qPCR and western blot, respectively. We found that lncRNA XIST was low-expressed, miR-212-3p was over-expressed, and RASA1 was dramatically down-regulated in KGN cells. LncRNA XIST negatively regulated miR-212-3p expression in KGN cells. MiR-212-3p interacted with RASA1 and negatively regulated RASA1 levels in KGN cells. Up-regulation of lncRNA XIST signally decreased cells viability, stimulated more apoptotic cells, enhanced Bax expression, and depressed Bcl-2 level in KGN cells. However, these observations were abolished after miR-212-3p mimic treatment. Furthermore, miR-212-3p inhibitor significantly inhibited cell proliferation, enhanced more apoptotic cells, increased Bax expression, and decreased Bcl-2 level in KGN cells, and these effects were eliminated by RASA1-siRNA transfection. Our observations revealed that lncRNA XIST protects against PCOS through regulating miR-212-3p/RASA1 axis, suggesting that lncRNA XIST may be a promising therapeutic target for PCOS therapy.

Construction of LncRNA-mediated CeRNA network for investigating the immune pathogenesis of myocardial infarction.

Myocardial infarction (MI) is a cardiovascular disease that seriously threatens human health. However, an immune-related competitive endogenous RNA (ceRNA) network has not been reported in MI. The GSE66360, GSE19339, GSE97320, GSE61741, and GSE168281 datasets were acquired from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmiRNAs) from MI patients and healthy controls were screened and an immune-related ceRNA network was constructed. Furthermore, the key long noncoding RNAs(lncRNAs) highly related to the immune mechanism of MI were identified utilizing the random walk with restart algorithm. Finally, the expression of the hub genes was further verified in the GSE66360, GSE19339, and GSE97320 datasets, and quantitativereal-time polymerase chain reaction (qRT-PCR) was performed for the MI patients and healthy controls. A total of 184 differentially expressed immune-related genes(DE-IRGs) and 432 DE-miRNAs were obtained, and an immune-related ceRNA network comprising 1421 lncRNAs, 61 DE-miRNAs, and 139 DE-IRGs was constructed. According to the order of stress, betweenness, and closeness, NEAT1, KCNQ1OT1, and XIST were identified as key lncRNAs. Moreover, random walk with restart analysis also suggested that NEAT1, KCNQ1OT1, and XIST are key lncRNAs. Subsequently, a ceRNA network of 10 hub genes and 3 lncRNAs was constructed. Finally, we found that the expression of FCER1G and TYROBP significantly differed between MI patients and control individuals in the GSE66360, GSE19339, and GSE97320 datasets. qRT-PCR revealed that the expression of NEAT1, KCNQ1OT1, XIST, FCER1G, and TYROBP was significantly elevated in MI tissue samples compared to healthy control tissue samples. NEAT1, KCNQ1OT1, XIST, FCER1G, and TYROBP are involved in MI and can be used as molecular biomarkers for the screening and diagnosis of MI. Furthermore, the immune system plays an essential role in the onset and progression of MI.

LncRNA XIST promotes bladder cancer progression by modulating miR-129-5p/TNFSF10 axis

BackgroundThe differential expression, biological function, and ceRNA regulatory mechanism of lncRNA XIST in bladder cancer (BC) were investigated, and its clinical values for the early diagnosis of bladder cancer patients were elucidated.MethodsqRT-PCR was employed to detect the expression patterns of lncRNA XIST, miR-129-5p and TNFSF10. The biological functions were measured by CCK8 assay, wound healing assay and transwell assay. Bioinformatics analysis and Dual-Luciferase reporter assay were employed to evaluate the interactions between the lncRNA XIST, miR-129-5p and TNFSF10.ResultsLncRNA XIST and TNFSF10 were highly expressed and miR-129-5p was low expressed (P < 0.05) in bladder cancer cell line. The depletion of lncRNA XIST inhibited BC proliferation, migration and invasion. Mechanistically, lncRNA XIST could sponge miR-129-5p to regulate TNFSF10 expression in bladder cancer. Furthermore, compared with adjacent tissues, lncRNA XIST and miR-129-5p were lowly expressed (P < 0.01) in bladder cancer tissues, and TNFSF10 was highly expressed (P < 0.001). miR-129-5p and TNFSF10 were associated with the risk of bladder cancer (P < 0.05); the difference in AUC values for the diagnosis of bladder cancer by lncRNA XIST (AUC = 0.739), miR-129-5p (AUC = 0.850) and TNFSF10 (AUC = 0.753) was statistically significant (P < 0.01), and the three genes combined AUC was 0.900, 95%CI was 0.842–0.958 with a sensitivity of 83.3% and specificity of 86.7%.ConclusionXIST, an elevated lncRNA in bladder cancer, inhibition of which could suppress the progression of BC. LncRNA XIST and miR-129-5p could form ceRNA to regulate the expression of TNFSF10.